Regulatory Effects of 198-bp Structural Variants in the Promoter Region on Adipogenesis in Chickens.

Molecular breeding accelerates animal breeding and improves efficiency by utilizing genetic mutations. Structural variations (SVs), a significant source of genetic mutations, have a greater impact on phenotypic variation than SNPs. Understanding SV functional mechanisms and obtaining precise information are crucial for molecular breeding. In this study, association analysis revealed significant correlations between 198-bp SVs in the promoter region and abdominal fat weight, intramuscular fat content, and subcutaneous fat thickness in chickens. High expression of in adipose tissue was positively correlated with the abdominal fat percentage, and different genotypes of exhibited varied expression patterns in the liver. The 198-bp SVs regulate expression by binding to different transcription factors. Overexpression of promoted preadipocyte proliferation and differentiation, while interference had the opposite effect. Mechanistically, the 198-bp fragment contains binding sites for transcription factors such as C/EBPα that regulate expression and fat synthesis. These SVs are significantly associated with chicken fat traits, positively influencing preadipocyte development by regulating cell proliferation and differentiation. Our work provides compelling evidence for the use of 198-bp SVs in the promoter region as molecular markers for poultry breeding and offers new insights into the pivotal role of the gene in fat generation.